Q: Thermostat reading high, car hard to start

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My car will give me problems when trying to start it. Sometimes it will turn on without a problem. On other occasions I would have to sit in the car for about 15-20 minutes before the engine actually comes on. Today, while driving, I noticed the thermostat reading was high, it was all the way up in the red zone. When I opened the hood the engine was very hot. About 2 days ago the engine was smoking a little but I didn't notice any changes in the thermostat. I towed it to a shop and they ran some test and said everything is fine but I'm here still wondering why the car won't start without a problem and why is my thermostat reading so high.
My car has an automatic transmission.

Hi, thanks for writing in. There are a few reasons why this may happen such as a faulty or stuck thermostat, coolant fan switches that are not working or potentially a blown head gasket. I recommend checking the coolant to see if you find any traces of oil in it. Also, try checking the oil to see if you find any traces of water in it. If either of those are true, then you may have a blown head gasket.

If you would like help, consider having an expert automotive technician from YourMechanic come to your home or office to inspect and diagnose this issue for you, and make or suggest any repairs as needed.

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